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James Yang5b4da322008-08-26 15:01:27 -05001/*
2 * Copyright 2008 Freescale Semiconductor, Inc.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * Version 2 as published by the Free Software Foundation.
7 */
8
9#ifndef _DDR_SPD_H_
10#define _DDR_SPD_H_
11
12/*
13 * Format from "JEDEC Standard No. 21-C,
14 * Appendix D: Rev 1.0: SPD's for DDR SDRAM
15 */
16typedef struct ddr1_spd_eeprom_s {
17 unsigned char info_size; /* 0 # bytes written into serial memory */
18 unsigned char chip_size; /* 1 Total # bytes of SPD memory device */
19 unsigned char mem_type; /* 2 Fundamental memory type */
20 unsigned char nrow_addr; /* 3 # of Row Addresses on this assembly */
21 unsigned char ncol_addr; /* 4 # of Column Addrs on this assembly */
22 unsigned char nrows; /* 5 Number of DIMM Banks */
23 unsigned char dataw_lsb; /* 6 Data Width of this assembly */
24 unsigned char dataw_msb; /* 7 ... Data Width continuation */
25 unsigned char voltage; /* 8 Voltage intf std of this assembly */
26 unsigned char clk_cycle; /* 9 SDRAM Cycle time @ CL=X */
27 unsigned char clk_access; /* 10 SDRAM Access from Clk @ CL=X (tAC) */
28 unsigned char config; /* 11 DIMM Configuration type */
29 unsigned char refresh; /* 12 Refresh Rate/Type */
30 unsigned char primw; /* 13 Primary SDRAM Width */
31 unsigned char ecw; /* 14 Error Checking SDRAM width */
32 unsigned char min_delay; /* 15 for Back to Back Random Address */
33 unsigned char burstl; /* 16 Burst Lengths Supported */
34 unsigned char nbanks; /* 17 # of Banks on SDRAM Device */
35 unsigned char cas_lat; /* 18 CAS# Latencies Supported */
36 unsigned char cs_lat; /* 19 CS# Latency */
37 unsigned char write_lat; /* 20 Write Latency (aka Write Recovery) */
38 unsigned char mod_attr; /* 21 SDRAM Module Attributes */
39 unsigned char dev_attr; /* 22 SDRAM Device Attributes */
40 unsigned char clk_cycle2; /* 23 Min SDRAM Cycle time @ CL=X-0.5 */
41 unsigned char clk_access2; /* 24 SDRAM Access from
Wolfgang Denkec7fbf52013-10-04 17:43:24 +020042 Clk @ CL=X-0.5 (tAC) */
James Yang5b4da322008-08-26 15:01:27 -050043 unsigned char clk_cycle3; /* 25 Min SDRAM Cycle time @ CL=X-1 */
44 unsigned char clk_access3; /* 26 Max Access from Clk @ CL=X-1 (tAC) */
45 unsigned char trp; /* 27 Min Row Precharge Time (tRP)*/
46 unsigned char trrd; /* 28 Min Row Active to Row Active (tRRD) */
47 unsigned char trcd; /* 29 Min RAS to CAS Delay (tRCD) */
48 unsigned char tras; /* 30 Minimum RAS Pulse Width (tRAS) */
49 unsigned char bank_dens; /* 31 Density of each bank on module */
50 unsigned char ca_setup; /* 32 Addr + Cmd Setup Time Before Clk */
51 unsigned char ca_hold; /* 33 Addr + Cmd Hold Time After Clk */
52 unsigned char data_setup; /* 34 Data Input Setup Time Before Strobe */
53 unsigned char data_hold; /* 35 Data Input Hold Time After Strobe */
54 unsigned char res_36_40[5];/* 36-40 reserved for VCSDRAM */
55 unsigned char trc; /* 41 Min Active to Auto refresh time tRC */
56 unsigned char trfc; /* 42 Min Auto to Active period tRFC */
57 unsigned char tckmax; /* 43 Max device cycle time tCKmax */
58 unsigned char tdqsq; /* 44 Max DQS to DQ skew (tDQSQ max) */
59 unsigned char tqhs; /* 45 Max Read DataHold skew (tQHS) */
60 unsigned char res_46; /* 46 Reserved */
61 unsigned char dimm_height; /* 47 DDR SDRAM DIMM Height */
62 unsigned char res_48_61[14]; /* 48-61 Reserved */
63 unsigned char spd_rev; /* 62 SPD Data Revision Code */
64 unsigned char cksum; /* 63 Checksum for bytes 0-62 */
65 unsigned char mid[8]; /* 64-71 Mfr's JEDEC ID code per JEP-106 */
66 unsigned char mloc; /* 72 Manufacturing Location */
67 unsigned char mpart[18]; /* 73 Manufacturer's Part Number */
68 unsigned char rev[2]; /* 91 Revision Code */
69 unsigned char mdate[2]; /* 93 Manufacturing Date */
70 unsigned char sernum[4]; /* 95 Assembly Serial Number */
71 unsigned char mspec[27]; /* 99-127 Manufacturer Specific Data */
72
73} ddr1_spd_eeprom_t;
74
75/*
76 * Format from "JEDEC Appendix X: Serial Presence Detects for DDR2 SDRAM",
77 * SPD Revision 1.2
78 */
79typedef struct ddr2_spd_eeprom_s {
80 unsigned char info_size; /* 0 # bytes written into serial memory */
81 unsigned char chip_size; /* 1 Total # bytes of SPD memory device */
82 unsigned char mem_type; /* 2 Fundamental memory type */
83 unsigned char nrow_addr; /* 3 # of Row Addresses on this assembly */
84 unsigned char ncol_addr; /* 4 # of Column Addrs on this assembly */
85 unsigned char mod_ranks; /* 5 Number of DIMM Ranks */
86 unsigned char dataw; /* 6 Module Data Width */
87 unsigned char res_7; /* 7 Reserved */
88 unsigned char voltage; /* 8 Voltage intf std of this assembly */
89 unsigned char clk_cycle; /* 9 SDRAM Cycle time @ CL=X */
90 unsigned char clk_access; /* 10 SDRAM Access from Clk @ CL=X (tAC) */
91 unsigned char config; /* 11 DIMM Configuration type */
92 unsigned char refresh; /* 12 Refresh Rate/Type */
93 unsigned char primw; /* 13 Primary SDRAM Width */
94 unsigned char ecw; /* 14 Error Checking SDRAM width */
95 unsigned char res_15; /* 15 Reserved */
96 unsigned char burstl; /* 16 Burst Lengths Supported */
97 unsigned char nbanks; /* 17 # of Banks on Each SDRAM Device */
98 unsigned char cas_lat; /* 18 CAS# Latencies Supported */
99 unsigned char mech_char; /* 19 DIMM Mechanical Characteristics */
100 unsigned char dimm_type; /* 20 DIMM type information */
101 unsigned char mod_attr; /* 21 SDRAM Module Attributes */
102 unsigned char dev_attr; /* 22 SDRAM Device Attributes */
103 unsigned char clk_cycle2; /* 23 Min SDRAM Cycle time @ CL=X-1 */
104 unsigned char clk_access2; /* 24 SDRAM Access from Clk @ CL=X-1 (tAC) */
105 unsigned char clk_cycle3; /* 25 Min SDRAM Cycle time @ CL=X-2 */
106 unsigned char clk_access3; /* 26 Max Access from Clk @ CL=X-2 (tAC) */
107 unsigned char trp; /* 27 Min Row Precharge Time (tRP)*/
108 unsigned char trrd; /* 28 Min Row Active to Row Active (tRRD) */
109 unsigned char trcd; /* 29 Min RAS to CAS Delay (tRCD) */
110 unsigned char tras; /* 30 Minimum RAS Pulse Width (tRAS) */
111 unsigned char rank_dens; /* 31 Density of each rank on module */
112 unsigned char ca_setup; /* 32 Addr+Cmd Setup Time Before Clk (tIS) */
113 unsigned char ca_hold; /* 33 Addr+Cmd Hold Time After Clk (tIH) */
114 unsigned char data_setup; /* 34 Data Input Setup Time
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200115 Before Strobe (tDS) */
James Yang5b4da322008-08-26 15:01:27 -0500116 unsigned char data_hold; /* 35 Data Input Hold Time
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200117 After Strobe (tDH) */
James Yang5b4da322008-08-26 15:01:27 -0500118 unsigned char twr; /* 36 Write Recovery time tWR */
119 unsigned char twtr; /* 37 Int write to read delay tWTR */
120 unsigned char trtp; /* 38 Int read to precharge delay tRTP */
121 unsigned char mem_probe; /* 39 Mem analysis probe characteristics */
122 unsigned char trctrfc_ext; /* 40 Extensions to trc and trfc */
123 unsigned char trc; /* 41 Min Active to Auto refresh time tRC */
124 unsigned char trfc; /* 42 Min Auto to Active period tRFC */
125 unsigned char tckmax; /* 43 Max device cycle time tCKmax */
126 unsigned char tdqsq; /* 44 Max DQS to DQ skew (tDQSQ max) */
127 unsigned char tqhs; /* 45 Max Read DataHold skew (tQHS) */
128 unsigned char pll_relock; /* 46 PLL Relock time */
129 unsigned char Tcasemax; /* 47 Tcasemax */
130 unsigned char psiTAdram; /* 48 Thermal Resistance of DRAM Package from
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200131 Top (Case) to Ambient (Psi T-A DRAM) */
James Yang5b4da322008-08-26 15:01:27 -0500132 unsigned char dt0_mode; /* 49 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200133 due to Activate-Precharge/Mode Bits
James Yang5b4da322008-08-26 15:01:27 -0500134 (DT0/Mode Bits) */
135 unsigned char dt2n_dt2q; /* 50 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200136 due to Precharge/Quiet Standby
James Yang5b4da322008-08-26 15:01:27 -0500137 (DT2N/DT2Q) */
138 unsigned char dt2p; /* 51 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200139 due to Precharge Power-Down (DT2P) */
James Yang5b4da322008-08-26 15:01:27 -0500140 unsigned char dt3n; /* 52 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200141 due to Active Standby (DT3N) */
James Yang5b4da322008-08-26 15:01:27 -0500142 unsigned char dt3pfast; /* 53 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200143 due to Active Power-Down with
James Yang5b4da322008-08-26 15:01:27 -0500144 Fast PDN Exit (DT3Pfast) */
145 unsigned char dt3pslow; /* 54 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200146 due to Active Power-Down with Slow
James Yang5b4da322008-08-26 15:01:27 -0500147 PDN Exit (DT3Pslow) */
148 unsigned char dt4r_dt4r4w; /* 55 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200149 due to Page Open Burst Read/DT4R4W
James Yang5b4da322008-08-26 15:01:27 -0500150 Mode Bit (DT4R/DT4R4W Mode Bit) */
151 unsigned char dt5b; /* 56 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200152 due to Burst Refresh (DT5B) */
James Yang5b4da322008-08-26 15:01:27 -0500153 unsigned char dt7; /* 57 DRAM Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200154 due to Bank Interleave Reads with
James Yang5b4da322008-08-26 15:01:27 -0500155 Auto-Precharge (DT7) */
156 unsigned char psiTApll; /* 58 Thermal Resistance of PLL Package form
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200157 Top (Case) to Ambient (Psi T-A PLL) */
James Yang5b4da322008-08-26 15:01:27 -0500158 unsigned char psiTAreg; /* 59 Thermal Reisitance of Register Package
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200159 from Top (Case) to Ambient
James Yang5b4da322008-08-26 15:01:27 -0500160 (Psi T-A Register) */
161 unsigned char dtpllactive; /* 60 PLL Case Temperature Rise from Ambient
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200162 due to PLL Active (DT PLL Active) */
James Yang5b4da322008-08-26 15:01:27 -0500163 unsigned char dtregact; /* 61 Register Case Temperature Rise from
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200164 Ambient due to Register Active/Mode Bit
James Yang5b4da322008-08-26 15:01:27 -0500165 (DT Register Active/Mode Bit) */
166 unsigned char spd_rev; /* 62 SPD Data Revision Code */
167 unsigned char cksum; /* 63 Checksum for bytes 0-62 */
168 unsigned char mid[8]; /* 64 Mfr's JEDEC ID code per JEP-106 */
169 unsigned char mloc; /* 72 Manufacturing Location */
170 unsigned char mpart[18]; /* 73 Manufacturer's Part Number */
171 unsigned char rev[2]; /* 91 Revision Code */
172 unsigned char mdate[2]; /* 93 Manufacturing Date */
173 unsigned char sernum[4]; /* 95 Assembly Serial Number */
174 unsigned char mspec[27]; /* 99-127 Manufacturer Specific Data */
175
176} ddr2_spd_eeprom_t;
177
178typedef struct ddr3_spd_eeprom_s {
179 /* General Section: Bytes 0-59 */
180 unsigned char info_size_crc; /* 0 # bytes written into serial memory,
181 CRC coverage */
182 unsigned char spd_rev; /* 1 Total # bytes of SPD mem device */
183 unsigned char mem_type; /* 2 Key Byte / Fundamental mem type */
184 unsigned char module_type; /* 3 Key Byte / Module Type */
185 unsigned char density_banks; /* 4 SDRAM Density and Banks */
186 unsigned char addressing; /* 5 SDRAM Addressing */
Dave Liu4be87b22009-03-14 12:48:30 +0800187 unsigned char module_vdd; /* 6 Module nominal voltage, VDD */
James Yang5b4da322008-08-26 15:01:27 -0500188 unsigned char organization; /* 7 Module Organization */
189 unsigned char bus_width; /* 8 Module Memory Bus Width */
190 unsigned char ftb_div; /* 9 Fine Timebase (FTB)
191 Dividend / Divisor */
192 unsigned char mtb_dividend; /* 10 Medium Timebase (MTB) Dividend */
193 unsigned char mtb_divisor; /* 11 Medium Timebase (MTB) Divisor */
194 unsigned char tCK_min; /* 12 SDRAM Minimum Cycle Time */
195 unsigned char res_13; /* 13 Reserved */
196 unsigned char caslat_lsb; /* 14 CAS Latencies Supported,
197 Least Significant Byte */
198 unsigned char caslat_msb; /* 15 CAS Latencies Supported,
199 Most Significant Byte */
200 unsigned char tAA_min; /* 16 Min CAS Latency Time */
201 unsigned char tWR_min; /* 17 Min Write REcovery Time */
202 unsigned char tRCD_min; /* 18 Min RAS# to CAS# Delay Time */
203 unsigned char tRRD_min; /* 19 Min Row Active to
204 Row Active Delay Time */
205 unsigned char tRP_min; /* 20 Min Row Precharge Delay Time */
206 unsigned char tRAS_tRC_ext; /* 21 Upper Nibbles for tRAS and tRC */
207 unsigned char tRAS_min_lsb; /* 22 Min Active to Precharge
208 Delay Time */
209 unsigned char tRC_min_lsb; /* 23 Min Active to Active/Refresh
210 Delay Time, LSB */
211 unsigned char tRFC_min_lsb; /* 24 Min Refresh Recovery Delay Time */
212 unsigned char tRFC_min_msb; /* 25 Min Refresh Recovery Delay Time */
213 unsigned char tWTR_min; /* 26 Min Internal Write to
214 Read Command Delay Time */
215 unsigned char tRTP_min; /* 27 Min Internal Read to Precharge
216 Command Delay Time */
217 unsigned char tFAW_msb; /* 28 Upper Nibble for tFAW */
218 unsigned char tFAW_min; /* 29 Min Four Activate Window
219 Delay Time*/
220 unsigned char opt_features; /* 30 SDRAM Optional Features */
221 unsigned char therm_ref_opt; /* 31 SDRAM Thermal and Refresh Opts */
York Sun72bdc802011-05-27 07:32:50 +0800222 unsigned char therm_sensor; /* 32 Module Thermal Sensor */
223 unsigned char device_type; /* 33 SDRAM device type */
York Sun794c6922012-08-17 08:22:37 +0000224 int8_t fine_tCK_min; /* 34 Fine offset for tCKmin */
225 int8_t fine_tAA_min; /* 35 Fine offset for tAAmin */
226 int8_t fine_tRCD_min; /* 36 Fine offset for tRCDmin */
227 int8_t fine_tRP_min; /* 37 Fine offset for tRPmin */
228 int8_t fine_tRC_min; /* 38 Fine offset for tRCmin */
229 unsigned char res_39_59[21]; /* 39-59 Reserved, General Section */
James Yang5b4da322008-08-26 15:01:27 -0500230
231 /* Module-Specific Section: Bytes 60-116 */
232 union {
233 struct {
234 /* 60 (Unbuffered) Module Nominal Height */
235 unsigned char mod_height;
236 /* 61 (Unbuffered) Module Maximum Thickness */
237 unsigned char mod_thickness;
238 /* 62 (Unbuffered) Reference Raw Card Used */
239 unsigned char ref_raw_card;
240 /* 63 (Unbuffered) Address Mapping from
241 Edge Connector to DRAM */
242 unsigned char addr_mapping;
243 /* 64-116 (Unbuffered) Reserved */
244 unsigned char res_64_116[53];
245 } unbuffered;
246 struct {
247 /* 60 (Registered) Module Nominal Height */
248 unsigned char mod_height;
249 /* 61 (Registered) Module Maximum Thickness */
250 unsigned char mod_thickness;
251 /* 62 (Registered) Reference Raw Card Used */
252 unsigned char ref_raw_card;
yorkde879322010-07-02 22:25:55 +0000253 /* 63 DIMM Module Attributes */
254 unsigned char modu_attr;
255 /* 64 RDIMM Thermal Heat Spreader Solution */
256 unsigned char thermal;
257 /* 65 Register Manufacturer ID Code, Least Significant Byte */
258 unsigned char reg_id_lo;
259 /* 66 Register Manufacturer ID Code, Most Significant Byte */
260 unsigned char reg_id_hi;
261 /* 67 Register Revision Number */
262 unsigned char reg_rev;
263 /* 68 Register Type */
264 unsigned char reg_type;
265 /* 69-76 RC1,3,5...15 (MS Nibble) / RC0,2,4...14 (LS Nibble) */
266 unsigned char rcw[8];
James Yang5b4da322008-08-26 15:01:27 -0500267 } registered;
268 unsigned char uc[57]; /* 60-116 Module-Specific Section */
269 } mod_section;
270
271 /* Unique Module ID: Bytes 117-125 */
272 unsigned char mmid_lsb; /* 117 Module MfgID Code LSB - JEP-106 */
273 unsigned char mmid_msb; /* 118 Module MfgID Code MSB - JEP-106 */
274 unsigned char mloc; /* 119 Mfg Location */
275 unsigned char mdate[2]; /* 120-121 Mfg Date */
276 unsigned char sernum[4]; /* 122-125 Module Serial Number */
277
278 /* CRC: Bytes 126-127 */
279 unsigned char crc[2]; /* 126-127 SPD CRC */
280
281 /* Other Manufacturer Fields and User Space: Bytes 128-255 */
282 unsigned char mpart[18]; /* 128-145 Mfg's Module Part Number */
283 unsigned char mrev[2]; /* 146-147 Module Revision Code */
284
285 unsigned char dmid_lsb; /* 148 DRAM MfgID Code LSB - JEP-106 */
286 unsigned char dmid_msb; /* 149 DRAM MfgID Code MSB - JEP-106 */
287
288 unsigned char msd[26]; /* 150-175 Mfg's Specific Data */
289 unsigned char cust[80]; /* 176-255 Open for Customer Use */
290
291} ddr3_spd_eeprom_t;
292
293extern unsigned int ddr1_spd_check(const ddr1_spd_eeprom_t *spd);
294extern void ddr1_spd_dump(const ddr1_spd_eeprom_t *spd);
295extern unsigned int ddr2_spd_check(const ddr2_spd_eeprom_t *spd);
296extern void ddr2_spd_dump(const ddr2_spd_eeprom_t *spd);
Dave Liu4be87b22009-03-14 12:48:30 +0800297extern unsigned int ddr3_spd_check(const ddr3_spd_eeprom_t *spd);
James Yang5b4da322008-08-26 15:01:27 -0500298
299/*
300 * Byte 2 Fundamental Memory Types.
301 */
302#define SPD_MEMTYPE_FPM (0x01)
303#define SPD_MEMTYPE_EDO (0x02)
304#define SPD_MEMTYPE_PIPE_NIBBLE (0x03)
305#define SPD_MEMTYPE_SDRAM (0x04)
306#define SPD_MEMTYPE_ROM (0x05)
307#define SPD_MEMTYPE_SGRAM (0x06)
308#define SPD_MEMTYPE_DDR (0x07)
309#define SPD_MEMTYPE_DDR2 (0x08)
310#define SPD_MEMTYPE_DDR2_FBDIMM (0x09)
311#define SPD_MEMTYPE_DDR2_FBDIMM_PROBE (0x0A)
312#define SPD_MEMTYPE_DDR3 (0x0B)
313
Kyle Moffett046d7722011-03-28 11:35:48 -0400314/* DIMM Type for DDR2 SPD (according to v1.3) */
315#define DDR2_SPD_DIMMTYPE_UNDEFINED (0x00)
316#define DDR2_SPD_DIMMTYPE_RDIMM (0x01)
317#define DDR2_SPD_DIMMTYPE_UDIMM (0x02)
318#define DDR2_SPD_DIMMTYPE_SO_DIMM (0x04)
319#define DDR2_SPD_DIMMTYPE_72B_SO_CDIMM (0x06)
320#define DDR2_SPD_DIMMTYPE_72B_SO_RDIMM (0x07)
321#define DDR2_SPD_DIMMTYPE_MICRO_DIMM (0x08)
322#define DDR2_SPD_DIMMTYPE_MINI_RDIMM (0x10)
323#define DDR2_SPD_DIMMTYPE_MINI_UDIMM (0x20)
324
325/* Byte 3 Key Byte / Module Type for DDR3 SPD */
326#define DDR3_SPD_MODULETYPE_MASK (0x0f)
327#define DDR3_SPD_MODULETYPE_RDIMM (0x01)
328#define DDR3_SPD_MODULETYPE_UDIMM (0x02)
329#define DDR3_SPD_MODULETYPE_SO_DIMM (0x03)
330#define DDR3_SPD_MODULETYPE_MICRO_DIMM (0x04)
331#define DDR3_SPD_MODULETYPE_MINI_RDIMM (0x05)
332#define DDR3_SPD_MODULETYPE_MINI_UDIMM (0x06)
Ira W. Snyder09da8b82011-11-21 13:20:33 -0800333#define DDR3_SPD_MODULETYPE_MINI_CDIMM (0x07)
334#define DDR3_SPD_MODULETYPE_72B_SO_UDIMM (0x08)
335#define DDR3_SPD_MODULETYPE_72B_SO_RDIMM (0x09)
336#define DDR3_SPD_MODULETYPE_72B_SO_CDIMM (0x0A)
337#define DDR3_SPD_MODULETYPE_LRDIMM (0x0B)
338#define DDR3_SPD_MODULETYPE_16B_SO_DIMM (0x0C)
339#define DDR3_SPD_MODULETYPE_32B_SO_DIMM (0x0D)
Dave Liu4be87b22009-03-14 12:48:30 +0800340
James Yang5b4da322008-08-26 15:01:27 -0500341#endif /* _DDR_SPD_H_ */